Answer / sunil guru

THE MAGNETIC FIELD FLUX HAS TO COMPETE THE RELUCTANCE AND RELUCTANCE IS DIRECTLY PROPORTIONAL TO THE AIR GAP ....
SO LESSER THE AIR GAP LESS IS THE LOSSES....

AIR GAP SHOULD BE LESS THAN 5 mm IN DC MC. AND LESS THAN 3 mm IN AC MACHINE

IF THE AIR GAP IS MORE THEN TO ESTABLISH THE MMF THE MACHINE WILL TAKE MORE CURRENT AND HENCE MORE IS THE LOSSES ....

FOR ANY DISAGREEMENT MAIL ME AT parmar20072008@yahoo.com

Answer / iamdon

The working flux travels through both the core and the air
gap.The ampere turn required to overcome the reluctance in
air gap is very large as compared to the iron or core
parts.In rotating machines, about 60-70 % of the total
ampere turns per pole are required for the air gap.So the
air gap length should be AS SMALL AS MECHANICALLY POSSIBLE.

Author:arbelectbit@yahoo.com

Answer / virendra

To reducet the leakage fulx

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